Manufacture of cream of tartar.



UNITED STATES "PATENT OFFICE.

JEAN MARIE PEBIGNY,

LYon, FRANCE, ASSIGNOR TO GALLIA, socrn'rn ANONYIIE,

or GENEVA, SWITZERLAND.

MANUFACTURE or CREAM or mama.

No Drawing.

To all whom it may concern:

Be it known that- I, JEAN MARIE PERIGNY, a citizen of the Republic ofFrance, residing at Lyon, France, have invented new andusefulImprovements in the Manufacture of Cream of Tartar, of which thefollowing is a specification.

This invention relates to a new process for the manufacture of cream oftartar from any crude. material containing tartrates (argol, wine lees,crystals from wine lees and from stills, grape skins or the like) and isbased on the variations of chemical equilibrium produced by. variationsof temperature in solutions of mixed salts. .The end in view being toincrease the solubility of bitartrate of potash in a hot liquor whilekeeping its solubility as low as "possible in a cold liquor, experimentshave proved that aluminium salts, and in particular the nitrate and thechlorid, give the best practical results. If, for example, bitartrate ofpotash is dissolved in a hot, chemically neutral solution of aluminiumchlorid or nitrate, the tartrate dissolves at the 'boiling point inquantity corresponding with the acid of the salt and oncooling andstirring nearly the whole of the bitartrate is deposited. The samereaction occurs even at high concentrations, and about 120 parts ofbitartrate can'be dissolved in 100 parts of liquid. As to the calciumtartrate which always exists in more or less considerable proportion inthe crude material, this also dissolves on boiling and it can beconverteddirectly into cream of tartar in the liquor by adding thecalculated proportion of an acid salt of potassium.

An exceedingly simple industrial ap lication of this process is, forexample, as ollows :Into a vat provided with a stirrer and a heatingdevice, there are introduced one cubic meter of the saline solutioncontaining 25 to 30 per cent. of chlorid of aluminum, and 1000 kilogramsof the crude material, containing per cent. of bitartrate, previouslyground to the degree of fineness necessary for procuring rapid andcomplete solution. The mixture is heated to boiling for about an hour,is then decolorized by animal charcoal or any other suitable means, andis finally pumped into a filter press. The presscake is washed withboiling water. The filtered liquor is run into stirring vats and'allowed to cool to deposit crystals of Specification of Letters Patent.Application filed November 14, 1911. seria no. 660,268.

Patented Apr. 16, 1912.

' bitartrate of potash, which are washed, and crushed. About 700kilograrnsof cream:

of tartar are thus obtained. The cold mother liquor is returned to theprocess. The white cream of tartar obtained by this single process isalways of a purityf of 99 per cent. at least. When the crude materialscontain notable quantities of sulfate of lime, it is useful to eliminatethis by the addition of baryta in order to obtain pure cream of tartar.A great advantage'ofthis process is that the salts ofaluminium, beingantiseptic, prevent any fermentation, even at the most favorabletemperature. ith argol, crystals and other rich materials, it is easy tooperate so as to obtain li uors containing 50 per cent. of bitartrate.ith poorer materials, the abundance of residue necessitates a lowerconcentration, but the boiling liquor leaving the filter press may beused for a fresh extraction and need not be run into the crystallizingvats until it contains the desired proportion of cream of tartardissolved in it. Finally, the other impurities, salts of iron, of lime,phosphoric acid and the like, which exist in small proportion in certaincrude materials and tend to accumulate in the mother liquors, areprecipitated from the latter from time to time by suitable reactions.

This new process includes the following principal advantages as comparedwith the old processes :(1) high conceutratiomtliu saving a notableamount of fuel. manual labor, power and material; (2) direct 0btainmentby a single solution and filtration of white and pure cream of tartarwith very small cost for decolorizing; (3) suppression of allfermentation of the liquors at all seasons; (4) almost complete absenceof mineral by-products, high yields and very small cost for liquids usedfor solution.

Having thus described the nature of this invention and the best means Iknow of carrying the same into practical effect, I claim I. A process ofmanufacturing cream of tartar from crude material containing tar trates,which process consists in heating the crude material with a solution ofa salt of aluminium. decolorizing the liquor, filtering it.crystalliziug the cream of tartar out of the liquor by cooling it, andutilizing the liquor fora new operation.

9. A process of manufacturing cream of tartar from crude mafierialcontdining t aftrates, wh1cl1 process consists in heating the crudematenal witha'solutlon of an aluininltwo subscribing W1 In testimonywhereof I have signed my tnesses.

v chlorid, decolorizing the liquor, filter- JEAN MARIE PERIGNY. 5 ingit, 4rysta.llizing the cream of tartar out Witnesses: fof; the liquor bycooling it, and finally using ALBERT VIARDOT,

the liquor for a new operatlon. PHILIPPE V nxos.

name to this specification in the presence of

